The present invention relates to the general field of thrust reversers for bypass turbojets. More particularly, it relates to an electromechanical thrust reverser comprising at least two displaceable elements co-operating in the open position of the reverser to reverse thrust, such as a grid, door, or shell thrust reverser.
Thrust reversers fitted to bypass turbojets are well known in the field of aviation. They are used to increase airplane safety by assisting in the braking thereof during landing. Thrust reversers are generally in the form of least two moving elements, such as sliding doors, which are suitable for being moved relative to the pod of the turbojet by means of control actuators so that when operating in thrust reversal, i.e. in the open position, they constitute an obstacle for a fraction of the gas coming from the turbojet, which fraction is redirected forwards so as to provide the airplane with reverse thrust.
In order to provide the control system of the thrust reverser with accurate information about the position in which the doors of the reverser are to be found, it is known to fit the doors with multiple position sensors that are directly connected to a reverser control unit. Generally, the sensors are positioned on each control actuator and are associated with detectors for detecting the state of each locking system of the reverser. Such sensors and detectors thus provide safety, enabling the pilot to be kept continuously informed about the deployed or retracted positions of the reverser doors.
Since a thrust reverser having two sliding doors generally comprises, for each door, three control actuators and three different locking systems, this leads to a large number of position sensors per reverser. Such an abundance of sensors has the effect of increasing the risk of there being a sensor breakdown, thereby reducing the reliability of the assembly as a whole. This abundance of sensors is also harmful in terms of the overall weight of the thrust reverser.
In addition, the position sensors that are generally used are abutment sensors that indicate only when the reverser is in a deployed position or in a retracted position. Such sensors do not enable sufficiently accurate information to be obtained concerning the exact positions of the doors of the reverser. In the event of one of the doors becoming blocked or jammed, it is difficult or even impossible to determine the exact position in which the thrust reverser is to be found.